Integrated automotive system, nozzle assembly and remote control method for cleaning an image sensors exterior or objective lens surface

ABSTRACT

An external lens washing system has an aiming fixture configured to support and constrain an external lens which is exposed to the elements and apt to become soiled with debris. A nozzle assembly is configured to be supported and aimed toward the external lens by the aiming fixture and has at least one laterally offset washing nozzle projecting from the aiming fixture to a spray washing fluid toward the external lens surface, spraying at a shallow, glancing spray aiming angle to impinge upon and wash the lens external surface. Optionally, an integrated image sensor and lens washing assembly is configured for use with a remote control method for cleaning an exterior objective lens surface and includes a sealed image sensor housing assembly including an integral, remotely controllable lens cleaning system with an optimized configuration for aiming one or more cleansing sprays from one or more laterally offset fluidic oscillators.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a Continuation of U.S. patent application Ser. No. 14/004,269filed on Nov. 18, 2013 entitled “INTEGRATED AUTOMOTIVE SYSTEM, NOZZLEASSEMBLY AND REMOTE CONTROL METHOD FOR CLEANING AN IMAGE SENSORSEXTERIOR OR OBJECTIVE LENS SURFACE,” which is National Phase Entry under35 U. S.C. 120 and 35 U.S.C. 111 (a) as a U.S. National Phase under 35USC 371 of PCT/US12/28828, filed Mar. 10, 2012, published, in English asWO/2012/138455 on Oct. 11, 2012 and also claims priority to USprovisional patent application 61/451,492 filed Mar. 10, 2011, theentire disclosures of which are expressly incorporated herein byreference.

FIELD OF THE INVENTION

The present invention relates to automated or remotely controlledmethods and apparatus for cleaning soiled objective lenses on videocameras or image sensors when mounted in a configuration that is exposedto dirty environments.

DISCUSSION OF THE PRIOR ART

External view (e.g., front bumper, side-view, rear-view or back-up)cameras have been added to recreational vehicles and automobiles toenhance the driver's vision and to improve safety. Increasingly, a widerange of cars and SUVs include integrated video cameras which generatean image for display to the driver, operator or other occupants or userswithin the vehicle's interior.

Drivers often find it difficult to move their vehicles from parkedpositions when they cannot see or know what is behind the vehicle. Therecent introductions of front-bumper, side-view and rear-view cameras incars and SUVs by vehicle manufacturers allow drivers to see whetherobstacles surround their vehicle using a display screen mounted eitheron a rear view mirror or in a navigation system screen.

The external image sensors such as those known as back-up or rear viewcameras are typically mounted unobtrusively, and incorporated intoexisting features such as the vehicle's rear name plate. These externalcameras are exposed to the vehicle's harsh environmental surroundingsand are often soiled by mud, salt spray or dirt which accumulates on thelens. Accumulating dirt and debris often distort the image drivers areviewing, thus creating confusion, dissatisfaction or a safety issue dueto poor judgment by relying on an unclear picture.

The advent of low cost, reliable imaging devices using solid-statesensor technologies (e.g., CMOS pixel sensor technology), combined withan improved cost/performance ratio for video displays capable of meetingautomotive specifications, and an increasing application rate of videomonitor displays for automotive navigation systems and the like, haslead to an increasing use of cameras or imaging sensors designed to givethe driver a view of those areas around the vehicle which are not in thenormal direct field of view of the driver, typically referred to as“blind spots”. These areas include the region close to the front of thevehicle, typically obscured by the forward structure of the vehicle, theregion along the passenger side of the vehicle, the region along thedriver's side of the vehicle rearward of the driver, and the area orregion immediately rearward of the vehicle which cannot be seen directlyor indirectly through the rear view mirror system. The camera or imagingsensor may capture an image of the rearward (or sideward or other blindspot area) field of view, and the image may be displayed to the driverof the vehicle to assist the driver in backing up or reversing orotherwise driving or maneuvering the vehicle.

The use of electronic cameras in vehicle imaging systems cansignificantly increase a diligent driver's knowledge of the spaceimmediately surrounding the vehicle prior to and during low speedmaneuvers, and thus contributes to the safe completion of suchmaneuvers. It is thus known to provide a camera or imaging sensor on avehicle for providing an image of an exterior scene for the driver. Sucha camera may be positioned within a protective housing, which may beclosed about the camera or sensor and secured together via fasteners orscrews or the like. For example, a metallic protective housing may beprovided, such as a die cast housing of aluminum or zinc or the like. Inparticular, for camera sensors mounted on the exterior of a vehicle,protection against environmental effects, such as rain, snow, roadsplash and/or the like, and physical protection, such as against roaddebris, dirt, dust, and/or the like, is important. Thus, for example, inknown exterior camera sensor mounts, a butyl seal, such as a hotdispensed butyl seal, or an 0-ring or other sealing member or materialor the like, has been provided between the parts of the housing toassist in sealing the housing to prevent water or other contaminantsfrom entering the housing and damaging the camera or sensor positionedtherein. However, such housings typically do not provide a substantiallywater tight seal, and water droplets thus may enter the housing.Furthermore, any excessive vibration of the camera sensor, due to itsplacement (such as at the exterior of the vehicle), may lead to anundesirable instability of the image displayed to the driver of thevehicle. Also, such cameras or sensors are costly to manufacture and toimplement on the vehicles.

Such vehicle vision systems often position a camera or imaging sensor atan exterior portion of a vehicle to capture an image of an exteriorscene. The cameras, particularly the cameras for rearward visionsystems, are thus typically placed or mounted in a location that tendsto get a high dirt buildup on the camera and/or lens of the camera, withno easy way of cleaning the camera and/or lens. In order to reduce thedirt or moisture buildup on the lenses of such cameras, prior artdevelopers proposed using hydrophilic or hydrophobic coatings on thelenses. However, the use of such a hydrophilic or hydrophobic coating onthe lens is not typically effective due to the lack of air flow acrossthe lens, especially within a sealed housing. It has also been proposedto use heating devices or elements to reduce moisture on the lenses,within the sealed housing. However, the use of a heated lens in suchapplications, while reducing condensation and misting on the lens, maypromote the forming of a film on the lens due to contamination that maybe present in the moisture or water. Also, the appearance of suchcameras on the rearward portion of vehicles is often a problem forstyling of the vehicle. See, for example, prior art U.S. Pat. No.7,965,336 to Bingle, et al. which discloses a camera module with aplastic housing that houses an image sensor, which is operable tocapture images of a scene occurring exteriorly of the vehicle. Bingle'scamera housing assembly is welded together with the image sensor andassociated components within enclosed the plastic housing, and includesa “breathable” ventilation portion that is at least partially permeableto water vapor to allow emission of internal water vapor substantiallyprecluding passage of water droplets and other contaminants, and soBingle's design seeks to minimize problems arising from fluid impactingor accumulating within the housing.

Bingle also seeks to use coated lenses to keep the objective lenses'view clear, and Bingle's housing or cover 22 is optionally be coatedwith an anti-wetting property such as via a hydrophobic coating (orstack of coatings), such as is disclosed in U.S. Pat. No. 5,724,187.Bingle notes that a hydrophobic property on the outermost surface of thecover can be achieved by a variety of means, such as by use of organicand inorganic coatings or by utilizing diamond-like carbon coatings. ButBingle and others do not propose actually taking any affirmative actionto remove road debris (e.g., accumulated dirt, dust, mud, road salt orother built-up debris) apart from using such coatings or surfacetreatments.

Based on consumer preference and at least a perceived improved abilityto extract information from the image, it is desired to present an imageto the driver that is representative of the exterior scene as perceivedby normal human vision. It is also desirable that a vehicle's imagingdevices or systems be useful in all conditions, and particularly in allweather and lighting conditions. However, it is often difficult toprovide an imaging sensor which is capable of providing a clear image inpoor weather, especially while driving. This is because conventionalimaging systems typically have difficulty resolving scene informationwhen the camera's objective lens is partially obstructed by accumulateddebris (e.g., accumulated dirt, dust, mud, road salt or other built-updebris).

In order to have effective use of the camera-based visibility systems inall weather conditions, it is desirable to have an effective method ofkeeping the camera lens (or the housing surface protecting the objectivelens) clean, but the potentially deleterious effects of moisture notedin Bingle remain. When driving or operating a vehicle during badweather, drivers are especially reluctant to exit the vehicle to findand inspect the camera's lens.

This reluctance likely explains why the inventors of US Patent 6,834,906(to Vaitus et al) included a “Nozzle” 92 “in close proximity to” lens 84for the vehicle's camera or vision unit 71. The Vaitus '904 patentgenerally discloses the structure and method for mounting a “VehicleLiftgate with Component Module Applique” wherein applique module 50 isadapted for attachment to vehicle liftgate 20 and, as shown in Vaitus'FIG. 2, module 50 includes a nozzle 92 which receives fluid from conduit94, but, as noted in the description at Col 5, lines 5-25, “cleaning oflens 84 may be implemented in other ways” such as hydrophobic lenscoatings. It appears that the module and nozzle arrangement described soindifferently in the Vaitus '904 patent was not deemed to be apracticable or effective solution meriting further development, and soappears to have been ignored.

There is a need, therefore, for a convenient, effective and unobtrusivesystem and method for cleaning an exterior objective lens surface, andpreferably by remote control.

OBJECTS AND SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to overcome theabove mentioned difficulties by providing a convenient, effective andunobtrusive system and method for cleaning an exterior objective lenssurface to remove accumulated debris (e.g., accumulated dirt, dust, mud,road salt or other built-up debris).

In accordance with the present invention, an external lens washingsystem has an aiming fixture configured to support and constrain anexternal lens which is exposed to the elements and apt to become soiledwith debris. A nozzle assembly is configured to be supported and aimedtoward the external lens by the aiming fixture and has at least onelaterally offset washing nozzle projecting from the aiming fixture to aspray washing fluid toward the external lens surface, spraying at ashallow, glancing spray aiming angle to impinge upon and wash the lensexternal surface.

Optionally, an integrated image sensor and lens washing assembly isconfigured for use with a remote control method for cleaning an exteriorobjective lens surface and includes a sealed image sensor housingassembly including an integral, remotely controllable lens cleaningsystem with an optimized configuration for aiming one or more cleansingsprays from one or more laterally offset fluidic oscillators.

The integrated automotive system uses one or more aimed sprays to cleanan exterior objective lens surface and the method enables the driver todetermine when to clean a soiled external-view camera's objective lens,so the driver can ensure that the lens is adequately cleaned ofaccumulated debris (e.g., accumulated dirt, dust, mud, road salt orother built-up debris) before moving.

The system of the present invention provides an image sensor housingassembly including an integral, remotely controllable lens cleaningsystem with an optimized configuration for aiming one or more cleaningsprays of selected fluidic oscillators at the housing's transparentobjective lens protective cover to safely and quickly remove accumulateddebris (e.g., accumulated dirt, dust, mud, road salt or other built-updebris) and minimize the likelihood that vision obstructing debris orwasher fluid droplets remain in the camera's field of view.

In a preferred embodiment of the lens cleaning system of the presentinvention, low flow rate fluidic circuit nozzles are configured andaimed in a manner which uses very little washing fluid. As a result,integrating the system of the present invention in a vehicle uses lesswashing fluid from the vehicle's washer fluid bottle and providesbottle-cleanings savings, conservation of fluid, and conservation ofpressure. Conservation of washer fluid pressure is especially importantwhen the camera lens cleaning system is integrated into an existingvehicle design's front wash system, where the camera lens washing systemmust function without detrimentally affecting front glass cleaning,especially under dynamic driving conditions, where the front glasscleaning system's performance is highly sensitive to fluid pressure. Thesystem and method of the present invention is not limited to use withlow flow rate nozzles exclusively, however. Applicants have prototyped arelatively high flow rate nozzle assembly on an exemplary system and itworks well, although the camera's image is somewhat compromised whenactually spraying fluid and washing. It appears that the low flow rateis best accomplished thru a selected fluidic circuit geometry whichallows washing fluid, since droplet size should remain larger whencompared to a shear nozzle.

Applicants' prototype development work has revealed that a certain lenswashing nozzle configuration and aiming orientation presents asurprisingly effective and evenly distributed oscillating spray patternwith the following benefits: Allows for nearly flush mounting to thecamera's distal or objective lens surface, which means thecamera-plus-washer package or assembly does not get longer andinterfere, or interfere as much, with camera viewing angles as adirected impact nozzle configuration would; and can be packaged inreally close to keep the overall width of the camera-plus-washer packagefrom growing wider and larger; (e.g., a wider or larger diameter bug-eyelens would likely need to have the nozzle spray originate above thelens, angled down, and pushed away from the center line to avoid sightlines, although this would result in a wider and longer package).

The applicants have discovered that directly spraying at a narrow,glancing angle nearly parallel to the objective lens assembly's externalsurface results in less washer fluid or water remaining on the lensafter conclusion of spraying and prevents water droplets from formingand remaining on the lens and obstructing the view after washing. Inprototype development experiments, a more nearly on-lens axis or directimpingement spray method was discovered to leave view-obstructingdroplets behind. In other prototype development work, applicants havealso noted that shear nozzles work surprisingly well.

Broadly speaking, the integrated automotive system and nozzle assemblyof the present invention is configured for use with a remote controlmethod for cleaning an exterior objective lens surface includes a sealedimage sensor housing assembly including an integral, remotelycontrollable lens cleaning system with an optimized configuration foraiming one or more cleansing sprays from selected fluidic oscillators atthe housing's transparent objective lens protective cover.

In use, a driver, user or operator views the image generated by theexternal camera or image sensor on an interior video display and decideswhether and when to clean the external camera's objective lens cover'ssurface to remove accumulated debris (e.g., accumulated dirt, dust, mud,road salt or other built-up debris). An interior remote actuationcontrol input (e.g., button or momentary contact switch) is providedwithin the operator's easy reach for convenient use in cleaning thelens, and the operator actuates the system and causes the cleansingspray to begin while viewing the image sensor's output on the videodisplay, stopping actuation of the system when the operator deems theimage sensor's view to be satisfactory.

The above and still further objects, features and advantages of thepresent invention will become apparent upon consideration of thefollowing detailed description of a specific embodiment thereof,particularly when taken in conjunction with the accompanying drawings,wherein like reference numerals in the various figures are utilized todesignate like components.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A, is a rear perspective view of a vehicle having an imagingsystem or back-up camera system as disclosed in U.S. Pat. No. 7,965,336(to Bingle et al), in accordance with the Prior Art.

FIG. 1B is a plan view of the vehicle of FIG. 1A.

FIG. 1C is an end elevation of a sealed solid-state image sensor orcamera module as disclosed in U.S. Pat. No. 7,965,336, in accordancewith the Prior Art.

FIG. 1D is a sectional view of the camera module of FIG. 1C, taken alongthe line D-D.

FIG. 2 is a schematic diagram illustrating an automotive imaging systemwith a camera housing and integrated nozzle assembly configured for usewith a remote control method for cleaning the imaging system's exteriorobjective lens surface, in accordance with the present invention.

FIGS. 3A-3D are photographs illustrating a configuration of anddisplayed performance of the imaging system, camera housing and an aimednozzle assembly, in accordance with the present invention.

FIG. 4 is a schematic diagram illustrating a fluidic spray from anembodiment of the camera housing and integrated nozzle assembly of FIG.3, in accordance with the present invention.

FIGS. 5A and 5B are schematic diagrams illustrating a perspective viewand a side view of a fluid sheet sprayed by an aimed nozzle assemblyconfigured for use with the method for cleaning an imaging system'sexterior objective lens surface, in accordance with the presentinvention.

FIGS. 6A and 6B are schematic diagrams illustrating a top or plan viewand a side view of an embodiment with opposing aimed washer fluid jetsspreading fluid over a convex objective lens surface when sprayed by anwashing system configured in accordance with the present invention.

FIG. 7 is a schematic diagram illustrating another automotive imagingsystem with a camera washing nozzle assembly configured for use with theremote control method for cleaning the imaging system's exteriorobjective lens surface, in accordance with the present invention.

FIG. 8 is a schematic diagram illustrating yet another automotiveimaging system configuration with a camera washing nozzle assemblyconfigured for use with the remote control method for cleaning theimaging system's exterior objective lens surface, in accordance with thepresent invention.

FIG. 9 is a perspective view illustrating aimed spray orientation foranother camera nozzle assembly configured for use with the method forcleaning the imaging system's exterior objective lens surface, inaccordance with the present invention.

FIG. 10 is a side view illustrating aimed spray fan angle and incidenceangle for the system and nozzle assembly of FIG. 9, in accordance withthe present invention.

FIG. 11 is a perspective view illustrating range of fluidic oscillatornozzle mounting distances for the system and nozzle assembly of FIGS. 9and 10, in accordance with the present invention.

FIGS. 12A and 12B illustrate the fluidic circuit features of anexemplary stepped mushroom fluid oscillator for use with an externalcamera lens cleaning nozzle assembly of the present invention.

FIG. 13A illustrates another embodiment for the external lens washingsystem and nozzle assembly of the present invention.

FIG. 13B illustrates a cross sectional view of the external lens washingsystem and nozzle assembly of the FIG. 13A.

FIG. 13C illustrates a cross sectional view of the external lens washingsystem and nozzle assembly of the FIG. 13A

DESCRIPTION OF THE PREFERRED EMBODIMENT

Vehicle Imaging System and Camera Module Nomenclature

In order to provide an exemplary context and basic nomenclature, werefer initially to FIGS. 1A-1D, illustrating a prior art imaging systemfor a vehicle and a camera module as disclosed in U.S. Pat. No.7,965,336 (to Bingle et al). This overview will be useful forestablishing nomenclature and automotive industry standard terminology,in accordance with the Prior Art.

Referring now to FIGS. 1A-1D, an image capture system or imaging orvision system 7 is positioned at a vehicle 8, such as at a rearwardexterior portion 8 a of the vehicle 8, and is operable to capture animage of a scene occurring interiorly or exteriorly of the vehicle, suchas rearwardly of the vehicle, and to display the image at a display ordisplay system 9 a of the vehicle which is viewable by a driver oroccupant of the vehicle (see, e.g., FIGS. 1A and 1B). Imaging system 7includes a camera module 10, which is mountable on, at or in the vehicleto receive an image of a scene occurring exteriorly or interiorly of thevehicle, and a control 9 b that is operable to process images capturedby an image sensor 18 of camera module 10. Camera module 10 includes aplastic camera housing 11 and a metallic protective shield or casing 16(see FIGS. 1C & 1D).

Camera housing 11 includes a camera housing portion 12 and a connectorportion 14, which mate or join together and are preferably laser weldedor sonic welded together to substantially seal the housing 11 tosubstantially limit or prevent water intrusion or other contaminantsfrom entering the housing, as discussed below.

Housing 11 of camera module 10 substantially encases a camera or imagesensor or sensing device 18 (FIGS. 1C and 1D), which is operable tocapture an image of the scene occurring exteriorly or interiorly of thevehicle, depending on the particular application of camera module 10.Housing 11 also includes a cover portion 20 at an end of camera housingportion 12. Cover portion 20 provides a transparent cover plate 22 whichallows the image of the scene exteriorly or interiorly of the vehicle topass therethrough and into housing 11 to camera image sensor 18. Cameramodule 10 may include the protective shield 16, which substantiallyencases camera housing portion 12 and a portion of connector portion 14,thereby substantially limiting or reducing electronic noise going intoor out of the camera module and/or protecting the plastic housing 11from damage due to impact or the like with various items or debris thatmay be encountered at the exterior of the vehicle.

Camera module 10 provides a camera image sensor or image capture device18 for capturing an image of a scene occurring exteriorly or interiorlyof a vehicle. The captured image may be communicated to a display ordisplay system 9 a which is operable to display the image to a driver ofthe vehicle. The camera or imaging sensor 18 useful with the presentinvention may comprise an imaging array sensor, such as a CMOS sensor ora CCD sensor or the like, such as disclosed in U.S. Pat. Nos. 5,550,677;5,670,935; 5,796,094; 6,097,023, and 7,339,149. Camera module 10 andimaging sensor 18 may be implemented and operated in connection withvarious vehicular vision systems, and/or may be operable utilizing theprinciples of such other vehicular systems, such as a vehicle visionsystem, such as a forwardly, sidewardly or rearwardly directed vehiclevision system utilizing principles disclosed in U.S. Pat. Nos.5,550,677; 5,670,935; 5,760,962; 5,877,897; 5,949,331; 6,222,447;6,302,545; 6,396,397; 6,498,620; 6,523,964; 6,611,202; and 6,201,642,and/or a trailer hitching aid or tow check system, such as the typedisclosed in U.S. Pat. No. 7,005,974, a reverse or sideward imagingsystem, such as for a lane change assistance system or lane departurewarning system, such as the type disclosed in U.S. Pat. No. 7,038,577, asystem for determining a distance to a leading or trailing vehicle orobject, such as a system utilizing the principles disclosed in U.S. Pat.No. 6,396,397 or the like.

For example, the camera or sensor may comprise a LM9618 Monochrome CMOSImage Sensor or a LM9628 Color CMOS Image Sensor, both of which arecommercially available from National Semiconductor. Other suitablecameras or sensors from other vendors (e.g., Sony®, Panasonic®, Magnaand others) may be implemented with the camera module.

Although shown at a rear portion 8 a of vehicle 8, camera 18 and cameramodule 10 may be positioned at any suitable location on vehicle 8, suchas within a rear panel or portion of the vehicle, a side panel orportion of the vehicle, a license plate mounting area of the vehicle, anexterior mirror assembly of the vehicle, an interior rearview mirrorassembly of the vehicle or any other location where the camera may bepositioned and oriented to provide the desired view of the sceneoccurring exteriorly or interiorly of the vehicle. The camera module 10is particularly suited for use as an exterior camera module. The imagecaptured by the camera may be displayed at a display screen or the likepositioned within the cabin of the vehicle, such as at an interiorrearview mirror assembly (such as disclosed in U.S. Pat. No. 6,690,268),or elsewhere at or within the vehicle cabin, such as by using theprinciples disclosed in U.S. Pat. Nos. 5,550,677; 5,670,935; 5,796,094;6,097,023 and 6,201,642, and/or U.S. Pat. No. 6,717,610.

As best shown in FIGS. 1C and 1D, camera housing portion 12 includes agenerally cylindrical portion 12 a extending outwardly from a baseportion 12 b. Camera housing portion 12 comprises a molded plasticcomponent and may include a pair of heater terminals or elements 30 a,30 b insert molded within and/or along the walls of cylindrical portion12 a. Cylindrical portion 12 a receives a lens or optic system 24therein, which functions to focus the image onto camera or sensor 18,which is positioned at a circuit board 26 mounted within the baseportion 12 b of camera housing portion 12.

Lens system 24 is positioned within cylindrical portion 12 a of cameraportion 12 to receive light from the exterior or interior scene throughcover 22 at end 12 c of camera portion 12. Lens system 24 is mounted to,such as via threaded engagement with, camera cover or housing 28, whichfunctions to substantially cover or encase camera or sensor 18 tosubstantially prevent or limit incident light from being received bycamera 18 and interfering with the image received by camera 18 throughcover 22 and lens system 24. The lens system 24 may be any small lens orlens system which may focus an image of the scene exteriorly of thecamera module onto the camera or image sensor 18, such as, for example,the types disclosed in U.S. Pat. No. 6,201,642 or U.S. Pat. No.6,757,109. The lens system 24 may provide a wide-angle field of view,such as approximately 120 degrees or more (as shown in FIG. 1A).

Cover portion 20 is mounted at an outer end 12 c of camera housingportion 12 opposite from base portion 12 b, as shown in FIGS. 1C and 1D.Cover portion 20 includes an outer circumferential ring or coverretainer 20 a, which engages an outer surface of transparent cover 22and functions to retain transparent cover 22 in position at the end 12 cof the cylindrical portion 12 a of camera receiving portion 12.Preferably, circumferential ring 20 a is laser welded or sonic welded orotherwise joined or bonded to outer end 12 c of cylindrical portion 12 aof camera receiving portion 12 to substantially seal and secures coverportion 20 onto camera receiving portion 12, and may limit orsubstantially preclude any water intrusion or contaminant intrusion intothe camera receiving portion at the outer end 12 c.

In the illustrated embodiment, base portion 12 b is generally square anddefines a generally square mating edge 12 e around the base portion 12 bfor mating and securing to a corresponding edge 14 g of connectorportion 14 at joint 13. Base portion 12 b receives circuit board 26 andcamera 18 therein, while a camera housing or shield 28 and lens or lenssystem 24 extend into cylindrical portion 12 a of camera portion 12 toreceive the image through transparent cover 22.

Connector portion 14 of housing 11 is a molded plastic component andincludes a connector terminal or connector 14 a, such as a multi-pinsnap-on connector or the like, extending from a base portion 14 b. Baseportion 14 b is formed (such as in a square shape as shown in theillustrated embodiment) to substantially and uniformly mate or connectto base portion 12 b of camera housing 12, as can be seen with referenceto FIGS. 1C and 1D. The base portions 12 b and 14 b mate together anddefine a pocket or space for receiving and securing circuit board 26therein. Base portions 14 b and 12 b may be laser welded or sonic weldedtogether at their mating joint or connection 13. Laser or sonic weldingof the joint melts the plastic edges or seams together to substantiallyhermetically seal housing 11 to prevent water intrusion or othercontaminant intrusion into housing 11 of camera module 10. Optionally,and less desirably, the base portions may be otherwise joined orsubstantially sealed together (such as via suitable adhesives and/orsealants). The module may optionally include a vented portion orsemi-permeable membrane to vent the module's interior. The base portions12 b and 14 b may further include mounting tabs or flanges 12 d, whichextend outwardly from base portion 12 b. Mounting tabs 12 d aregenerally aligned with one another when the base portions are securedtogether and include an aperture therethrough for mounting the cameramodule 10 at or to the vehicle 8 via suitable fasteners or the like (notshown). Although shown as having generally square-shaped matingportions, connector portion 14 and camera portion 12 may have othershaped mating portions or surfaces.

Multi-pin connector 14 a extends from base portion 14 b and includes aplurality of pins or terminals 14 c for electrically connecting cameramodule 10 with a connector (not shown) connected with the wiring harnessor cables of the vehicle. For example, one end 14 d of terminals 14 cmay connect to circuit board 26, while the other end 14 e of terminals14 c connects to the corresponding connector of the vehicle. Thecorresponding connector may partially receive the ends 14 e of pins orterminals 14 c at multi-pin connector 14 a and may snap together withmulti-pin connector 14 a via a snap connection or the like. As bestshown in FIG. 1D, ends 14 d of terminals 14 c protrude or extend fromconnector portion 14, such that the ends 14 d may be received withincorresponding openings or apertures 26 c in circuit board 26 whenhousing portion 11 is assembled.

As shown in FIG. 1D, connector portion 14 may provide a generallystraight multi-pin connector extending longitudinally from the baseportion of the housing 11. However, other shapes of connectors, such asangled connectors or bent connectors or the like, may be implemented,depending on the particular application of the camera module.

Optionally, camera module 10 may comprise a substantially hermeticallysealed module, such that water intrusion into the module is limited orsubstantially precluded. Base portion 12 b of camera housing portion 12and base portion 14 b of connector portion 14 are correspondingly formedso as to substantially mate or join together at their mating seam 13,whereby the portions may be laser welded or sonic welded together orotherwise joined, while cover portion 20 is also laser welded or sonicwelded or otherwise secured and substantially sealed at the opposite end12 c of camera portion 12, in order to substantially seal the camerahousing. Laser or sonic welding techniques are preferred so as to jointhe materials at a state where they are able to re-flow, either viaheat, vibration or other means, such that the materials re-flow andcross-link and become a unitary part. Such joining results in asubstantially hermetically sealed camera module. Additionally, the poresin the plastic as well as any voids around the insert molded pins andstampings may be sealed with a Loctite® brand sealing material or othersuitable sealing material, to further limit or substantially precludeentry of water droplets and/or water vapor into the housing of thesubstantially sealed camera module 10.

Circuit board 26 includes a camera mounting circuit board 26 a, which isconnected to a connector receiving circuit board 26 b via a multi-wireribbon wire or the like (not shown). Camera mounting circuit board 26 ais mounted or secured to the base portion 12 b of camera portion 12,while connector circuit board 26 b is mounted or secured to the baseportion 14 b of connector portion 14. Camera or image sensor 18 ismounted at a surface of camera circuit board 26 a, and is substantiallyencased at circuit board 26 a by camera cover 28 and lens 24 (FIGS. 1Cand 1D). Camera circuit board 26 a includes a pair of apertures 26 c forreceiving ends 30 c of terminals 30 a, 30 b. Likewise, connector circuitboard 26 b includes a plurality of openings or apertures 26 d forreceiving ends 14 d of connector terminals 14 c therethrough. The endsof the pins or terminals may be soldered in place in their respectiveopenings. After all of the connections are made, the housing may befolded to its closed position and laser welded or sonic welded togetheror otherwise joined or bonded together to substantially seal the circuitboard within the housing.

Optionally, the exterior surface of cover 22 (which may be exposed tothe atmosphere exterior of the camera module) may be coated with ananti-wetting property such as via a hydrophilic coating (or stack ofcoatings), such as is disclosed in U.S. Pat. Nos. 6,193,378; 5,854,708;6,071,606; and 6,013,372. Also, or otherwise, the exterior or outermostsurface of cover 22 may optionally be coated with an anti-wettingproperty such as via a hydrophobic coating (or stack of coatings), suchas is disclosed in U.S. Pat. No. 5,724,187. Such hydrophobic property onthe outermost surface of the cover can be achieved by a variety ofmeans, such as by use of organic and inorganic coatings utilizing asilicone moeity (for example, a urethane incorporating siliconemoeities) or by utilizing diamond-like carbon coatings. For example,long-term stable water-repellent and oil-repellent ultra-hydrophobiccoatings, such as described in WIPO PCT publication Nos. WO0192179 andWO0162682, can be disposed on the exterior surface of the cover. Suchultra-hydrophobic layers comprise a nano structured surface covered witha hydrophobic agent which is supplied by an underlying replenishmentlayer (such as is described in Classen et al., “Towards a True‘Non-Clean’ Property: Highly Durable Ultra-Hydrophobic Coating forOptical Applications”, ECC 2002 “Smart Coatings” Proceedings, 2002,181-190). For enablement and completeness of disclosure, all of theforegoing references are incorporated herein by reference.

In FIGS. 1A-1D, camera module 10 is shown to include a protectiveconductive shield or casing 16 which partially encases the plastichousing 11 and functions to limit or reduce electronic noise which mayenter or exit camera module 10 and may protect the plastic housing fromdamage from impact of various items or debris which the camera modulemay encounter at the exterior portion of the vehicle. The protectiveshield or casing 16 includes a pair of casing portions 16 a (one ofwhich is shown in FIGS. 1C and 1D). Each of the casing portions 16 apartially encases about half of the plastic housing 11 of camera module10 and partially overlaps the other of the casing portion 16 a, tosubstantially encase the plastic housing within protective shield 16.Each of the portions 16 a includes a slot 16 b for receiving themounting tabs 12 d therethrough for mounting the camera module at thedesired location at the vehicle. Each casing portion 16 a includesoverlapping portions 16 c which overlap an edge of the other casingportion 16 a to assemble the casing 16 around the plastic housing 11.The casing portions 16 a may be welded, crimped, adhered, banded, orotherwise joined or secured together about the plastic housing 11, inorder to encase the housing 11. Preferably, protective shield 16comprises a metallic shield and contacts ground terminal 30 b of heatingdevice 30 at the exterior surface of the cylindrical portion 12 a ofcamera receiving portion 12 and, thus, may be grounded to the heatingdevice and/or the camera module or unit via the ground terminal 30 b.Protective shield 16 may comprise a stamped metal shielding or may beformed by vacuum metalizing a shield layer over the plastic housing 11,or may comprise a foil or the like.

Camera Housing and Integrated Washing System Nozzle Assembly.

Referring now to FIGS. 2-13D, an exemplary embodiment of the presentinvention has an integrated camera housing and washing system nozzleassembly 110 and FIGS. 2-13D illustrate the method for cleaning acamera's or image sensor's exterior objective lens surface (e.g., 122),in accordance with the present invention. Integrated camera housing andnozzle assembly 110 preferably includes one or more laterally offsetnozzles 130, 132 configured and aimed to generate and an oscillatingspray to clean exterior objective lens surface 122, and allows avehicle's driver, user or operator to use interior display 9 a todetermine whether external-view camera objective lens surface or cover122 is occluded by or covered with accumulated debris (e.g., accumulateddirt, dust, mud, road salt or other built-up debris, not shown). Thedriver will want to ensure that the external objective lens surface 122is adequately cleaned before moving the vehicle 8. Laterally offsetnozzles 130, 132 are preferably entirely out of the image sensor'sdistal field of view and are configured and aimed to spray washing fluidonto external objective lens surface 122 at a narrow, glancing anglewhich is preferably nearly parallel to the objective lens assembly'sexternal surface 122, as will be described in more detail below.

Camera housing and nozzle assembly 110, as illustrated in FIG. 2 has anexternal housing 111 with a hollow interior enclosed withinfluid-impermeable sidewalls and a substantially, fluid impermeablesealed camera module 112 is carried within the interior of housing 111which defines an enclosure with an interior lumen or fluid path 140preferably configured to define least one fluidic oscillator thatoperates on a selectively actuated flow of pressurized fluid flowingthrough the oscillator's interior 140 to generate an exhaust flow in theform of an oscillating spray of fluid droplets (not shown), as will bedescribed below. The oscillator in fluid path 140 comprises a proximalinlet 142 for pressurized washer fluid, an interaction chamber definedwithin the housing fluid path 140 receives the pressurized washer fluidfrom inlet 142 and passes the pressurized fluid distally to outlets ornozzles 130, 132 so an oscillating washer fluid spray exhausts from theinteraction chamber 140. Fluidic oscillators can provide a wide range ofliquid spray patterns by cyclically deflecting a fluid jet. Theoperation of most fluidic oscillators is characterized by the cyclicdeflection of a fluid jet without the use of mechanical moving parts.Consequently, an advantage of fluidic oscillators is that they providean oscillating spray of fluid droplets but don't require moving partsand so are not subject to the wear and tear which adversely affects thereliability and operation of other oscillating spray devices.Alternatively, camera housing and nozzle assembly 110 may have afeatureless hollow interior lumen defining a cylindrical or annularfluid path from proximal fluid inlet 142 to an open distal shear nozzleadapted to spray external objective lens surface 122 with washer fluidat a narrow, glancing angle nearly parallel to the objective lensassembly's external surface 122.

Camera housing and nozzle assembly 110 preferably includes at least one“stepped mushroom” fluidic oscillator of the type described in commonlyowned U.S. Pat. No. 7,267,290 (Gopalan et al), the entire disclosure ofwhich is incorporated herein by reference. As shown in FIGS. 12A and 12B(and described more fully in the incorporated '290 patent's description)the stepped mushroom fluidic oscillator is defined by inwardlyprojecting features (not shown in FIG. 2) acting on the fluid flowingdistally in fluid path 140 which defines the interaction chamber withinthe housing fluid path 140. Washing fluid passes from proximal fluidinlet 142 distally into the interaction chamber 140 and the pressurizedoscillating fluid jets pass to outlets or nozzles 130, 132 from which anoscillating washer fluid spray projects laterally onto objective lenssurface 122. The preferred spray flow rate is approximately 200 ml/minper nozzle at 18 psi, and the spray thickness (i.e., which is seen inthe plane transverse to the spray's fan angle plane as shown in FIG. 5B)is approximately 2 degrees.

As illustrated in FIG. 2, external lens washing system with housing andnozzle assembly 110 provides a substantially rigid aiming fixture (i.e.,housing 111) having a distal side and a proximal side and beingconfigured to support and constrain external lens 122 which is exposedtoward the distal side. External lens 122 has an external lens surfacewith a lens perimeter and a lens central axis 150 projecting distallyfrom the lens surface, wherein a lens field of view is defined as adistally projecting solid angle (e.g., a truncated cone or pyramid, notshown) including the lens central axis 150 and originating within thelens perimeter. The washing system includes at least a first nozzleassembly 110 which is configured to be supported and aimed towardexternal lens 122 by the aiming fixture defined by housing 111, and thefirst nozzle assembly includes a barbed fitting for fluid inlet 142which is in fluid communication with a first laterally offset washingnozzle 132 which projects from the aiming fixture's distal side. Thefirst nozzle assembly 110 is configured and aimed to spray washing fluidtoward the external lens surface and across the field of view, sprayingat a first selected spray aiming angle (e.g., between 1° and 20°)relative to the plane of the lens external surface. The first nozzleassembly is oriented to spray from a selected side, meaning that it isaimed to spray along a first selected spray azimuth angle in relation toa selected fixed reference point or datum on the lens perimeter.

Optionally, the first laterally offset washing nozzle 130 is configuredas a non-oscillating shear nozzle configured to generate a substantiallyflat fan spray having a selected spray fan angle (e.g., 45° or anotherangled selected in the range of 15° to 120°). Alternatively, firstlaterally offset washing nozzle 130 may be configured as anon-oscillating bug-eye nozzle configured to generate at least onesubstantially solid fluid jet (i.e., a substantially solid fluid streamhaving no fan angle).

Preferably, the first laterally offset washing nozzle 130 is configuredto aim the laterally offset washing nozzle from a first selected lateraloffset distance from the center of the objective lens' external surface(e.g., the first selected lateral offset distance is preferably withinthe range bounded by 10 mm and 30 mm) for a spray having a fan angle inthe range of 15° to 120°.

Turning now to FIGS. 3A-3D and FIG. 4, FIGS. 3A-3D are photographsillustrating a configuration of and displayed “before and after”performance of an imaging system with a sealed camera housing 212 and anaimed nozzle assembly 210 with laterally offset nozzle 230, inaccordance with the present invention. FIG. 4 is a schematic diagramillustrating a fluidic spray 236 from camera housing 212 nozzle assembly210 with laterally offset nozzle 230, and FIGS. 5A and 5B are schematicdiagrams illustrating a perspective view and a side view of a fluidsheet 236 sprayed by an aimed nozzle 230 configured for the method forcleaning the imaging system's exterior objective lens surface 222, inaccordance with the present invention.

Returning to FIG. 3A, a soiled or dirty objective lens surface 222 hasbeen coated with a representative distribution of “SAE mud”, whichserves as a standard exemplar of a coating of road grime or debris 223.FIG. 3B is a photograph of the image generated by camera 212 whilecoated with debris 223 and the debris 223 is clearly obstructing thedisplayed view 209A as displayed to the user or driver. FIGS. 3C and 3Dare photographs illustrating the washing or debris removal effect of thesystem of the present invention, and illustrate (in FIG. 3C) that debris223 has been entirely removed from the distal surface of camera housing212 and lens surface 222 by spray 236. In addition, the user operatingthe washer system 210 has been able to actuate the system to spray fromaimed nozzle 230 while viewing displayed view 209A and so knows when tostop the washing, since debris 223 has been entirely removed from thedistal surface of camera housing 212 and is seen to no longer obstructlens surface 222.

As illustrated in FIGS. 3A-5B, external lens washing system 210 includesa substantially rigid aiming fixture having a distal side and a proximalside and being configured to support and constrain an external lens 222exposed toward the distal side; the external lens has an external lenssurface with a lens perimeter and a lens central axis 250 projectingdistally from the lens surface 222, wherein a lens field of view isdefined as a distally projecting solid angle (e.g., a truncated pyramid,encompassing the view in display 209A) including the lens central axis250 and originating within the lens perimeter. Washing system 210includes at least a first nozzle assembly configured to be supported andaimed toward the external lens 222 by the aiming fixture, and the firstnozzle assembly includes a fluid inlet (not shown) in fluidcommunication with a first laterally offset washing nozzle 230 whichprojects from the aiming fixture's distal side. The nozzle 230 isconfigured and aimed to spray washing fluid in a substantially planarsheet 236 having a selected thickness 255 toward the external lenssurface 222 and across the field of view, spraying at a first selectedspray aiming angle (i.e., preferably spraying in a plane inclinedproximally at an angle) of about 1°. The selected aiming angle can be ina range between 1° and 20° (as seen in FIGS. 4 and 5B) relative to aplane tangent to the lens external surface 222. Nozzle 230 is orientedto spray from a selected side, meaning that it is aimed to spray along afirst selected spray azimuth angle in relation to a selected fixedreference point or datum 251 on the lens perimeter.

Preferably, lens washing nozzle 230 includes a first fluidic oscillatorinteraction chamber configured to operate on a selectively actuated flowof pressurized washing fluid flowing through the first oscillator'schamber to generate a first exhaust flow of fluid droplets 236, and thefirst nozzle assembly's fluid inlet receives pressurized washer fluidand is in fluid communication with the first interaction chamber whichpasses the pressurized washer fluid distally to the first laterallyoffset outlet nozzle 230 which is configured to exhaust the washer fluidfrom the first interaction chamber and generate a first oscillatingspray of fluid droplets 236 aimed toward the external lens surface 222and across the field of view. Preferably that fluidic oscillator isconfigured as a stepped mushroom fluidic oscillator (as illustrated inFIGS. 12A and 12B). The preferred spray flow rate is approximately 200ml/min per nozzle at 18 psi, and the spray thickness 255 (i.e., which isseen as thickness in the spray plane transverse to the spray's fan angleplane, as shown in FIG. 5B) is preferably approximately 2 degrees. Theoscillating action and large drops generated by the fluidic oscillatoraimed by nozzle 230 in this manner were discovered to wet lens surface222 very rapidly and provided a kinetic impact effect which was found toimpact, flood and drive debris 223 as part of a flowing effluent 238laterally off lens surface 222.

Optionally, laterally offset washing nozzle 230 is configured as anon-oscillating shear nozzle configured to generate a substantially flatfan spray having a selected spray fan angle (e.g., 45° or another angledselected in the range of 15° to 120°. Alternatively, first laterallyoffset washing nozzle may be configured as a non-oscillating bug-eyenozzle configured to generate at least one substantially solid fluid jet(i.e., a substantially solid fluid stream having no fan angle).

Preferably, the first laterally offset washing nozzle 230 is configuredto aim the spray 236 from a first selected lateral offset distance (fromthe nozzle's throat or outlet to the center of objective lens' externalsurface 222) of about 15 mm. The selected lateral offset distance ispreferably within the range bounded by 10 mm and 30 mm, in order to keepthe entire package as compact as possible.

Some external camera systems include convex or dome-shaped lenssurfaces, which can be more difficult to clean. As shown in FIGS. 6A and6B, the system of the present invention can be configured with pluralnozzle assemblies to effectively clean different image sensor housingconfigurations and different external lens surface shapes. Optionally,as shown in FIGS. 6A and 6B, an external lens washing system 210 of FIG.3A-5B can include a second nozzle 232 configured to be supported andaimed by the aiming fixture, where the second nozzle 232 is configuredand aimed direct a second spray 237 along a second selected sprayazimuth angle being radially spaced at a selected inter-spray angle(e.g., 180°) from the first nozzle assembly's spray azimuth angle,aiming second spray 237 to oppose first spray 236.

For the external lens washing system illustrated in FIGS. 6A and 6B, thesecond nozzle assembly 232 preferably has a second fluidic oscillatorinteraction chamber configured to operate on a selectively actuated flowof pressurized washing fluid flowing through the second oscillator'schamber to generate the second exhaust flow of fluid droplets 237.Second nozzle assembly 232 receives pressurized washer fluid and is influid communication with the second interaction chamber which passes thepressurized washer fluid distally to the second laterally offsetnozzle's outlet or throat which is configured to exhaust the washerfluid from the second interaction chamber and generate the secondoscillating spray of fluid droplets 237 which is also aimed toward theexternal lens surface 222 and across the field of view. The secondfluidic oscillator is also preferably configured as a stepped mushroomfluidic oscillator.

Impinging fluid jets 236, 237 are aimed to create a specific hydrauliceffect and cooperate to distribute fluid across the lens surface in verylittle time. As the colliding and impinging fluid jets 236, 237 impactdebris 223 (not shown) and the lens surface the provided a kineticimpact effect which was found to dislodge, dissolve and drive debris asa turbulent flowing effluent 238 laterally off lens surface 222. Thepreferred spray flow rate for each nozzle 230, 232 is approximately 200ml/min per nozzle at 18 psi, and the spray thickness 255 (i.e., which isseen as thickness in the spray plane transverse to the spray's fan angleplane, as shown in FIGS. 5B and 6B) is preferably approximately 2degrees.

Optionally, second laterally offset washing nozzle 232 is configured asa non-oscillating shear nozzle configured to generate a substantiallyflat fan spray having a selected spray fan angle (e.g., 45° or anotherangled selected in the range of 15° to 120°. Alternatively, secondlaterally offset washing nozzle 232 may be configured as anon-oscillating bug-eye nozzle configured to generate at least onesubstantially solid fluid jet (i.e., a substantially solid fluid streamhaving no fan angle).

Preferably, the second laterally offset washing nozzle 232 is configuredto aim the spray 237 from a first selected lateral offset distance (fromthe nozzle's throat or outlet to the center of objective lens' externalsurface 222) of about 15 mm. The selected lateral offset distance ispreferably within the range bounded by 10 mm and 30 mm, in order to keepthe entire washing system's package as compact as possible.

Turning now to system diagrams 7 and 8, The lens washing system of thepresent invention is readily integrated into standard equipment alreadyspecified for inclusion in many automobiles and other vehicles (e.g.,8). As best seen in FIG. 7, vehicles (e.g., 8) configured with anexisting windshield washing system (“front wash”) or rear window washingsystem (“rear wash”) require use of a washing fluid reservoir andpumping system to provide a supply of pressurized washing fluid. Washertank or reservoir 290 typically includes an internal pump 292 which isactivated to draw washing fluid from the reservoir 290 and supplypressurized fluid to a conduit network 294 (e.g., comprising lumens,tubes or hoses) which supply the windshield washing nozzles 296 and rearwindow washing nozzle(s) 298. In accordance with one embodiment of thepresent invention, the system of the present invention (e.g., 110 or210) actuates lens washing in response to driver control input orautomatically. In automatic operation, lens washing is initiated ortriggered in response to the driver's use of the windshield washingsystem or “front wash” (e.g., where lens washing happens every time thewindshield is sprayed with front wash nozzle 296 or alternatively, lenswash may be selectively actuated periodically, with one momentary lenswash cycle for every 3-5 front wash events). Similarly, rear window orliftgate/backlight cleaning can be linked to the lens washing for aback-up camera system wherein backup camera lens washing happens everytime the rear window is sprayed with rear wash nozzle 298 oralternatively, a backup camera lens wash may be selectively actuatedperiodically, with one momentary lens wash cycle for every 3-5 rear washevents.

Alternatively, camera lens washing may be user-controlled using aninterior display (e.g., 9 a) wherein remotely controllable system 310includes at least one nozzle assembly 210 and configured to clean theexternal image sensor's objective lens surface and washing offaccumulated image distorting debris 223 uses the display mounted withinthe vehicle's interior 9A connected to the vehicle's data communicationnetwork to receive image signals for display to the driver. The externalimage sensor is configured to generate an external image display thesensor's external objective lens surface 222 is aimed toward thevehicle's exterior (e.g., rear, front or to the sides of vehicle 8) andthe sensor or camera has a selected field of view. The image sensorbeing substantially exposed to the ambient environment and accumulatedimage distorting debris when the vehicle is in use. The image sensorlens washing system is configured with laterally offset washing nozzle230 to selectively spray washing fluid onto the image sensor's objectivelens surface at a narrow, glancing angle, the spray being aimed acrossthe field of view along an aiming angle which is aimed at a selectedaiming angle that within the range bounded by 1° and 20° in relation tothe external objective lens surface, and the spray being actuated inresponse to a momentary wash control signal of a few seconds duration.The washing system actuation switch mounted within the interior ofvehicle 8 and is configured to selectively and momentarily generate thewash control signal when actuation of the lens washing system 210 isdesired by the driver, while viewing the display 9A.

Turning now to FIG. 8, The lens washing system of the present inventionis readily integrated into standard equipment already specified forinclusion in many automobiles and other vehicles (e.g., 8). A vehicles(e.g., 8) configured with a front wash system also requires use of awashing fluid reservoir and pumping system to provide a supply ofpressurized washing fluid. Washer tank or reservoir 290 has an internaldual outlet pump 293 which is activated to draw washing fluid from thereservoir 290 and supply pressurized fluid to a conduit network 294(e.g., comprising lumens, tubes or hoses) which supply the windshieldwashing nozzles 296 and via a rear or secondary outlet conduit, suppliescamera washing system 210. Pressurized fluid transmission to camerasystem 210 may be controlled either by selective actuation of pump 293or by control of one or more valves (not shown) placed to either allowor stop washer fluid flow to lens washing assembly 210.

In accordance with another embodiment of the system of the presentinvention, lens washing system 311 is actuated in response to drivercontrol input or automatically. In automatic operation, lens washing isinitiated or triggered in response to the driver's use of the windshieldwashing system or “front wash” (e.g., where lens washing happens everytime the windshield is sprayed with front wash nozzle 296 oralternatively, lens wash may be selectively actuated periodically, withone momentary lens wash cycle for every 3-5 front wash events).

Alternatively, for system 311, as illustrated in FIG. 8,camera lenswashing may be user-controlled using an interior display (e.g., 9 a)wherein remotely controllable system 311 includes at least one nozzleassembly 210 and configured to clean the external image sensor'sobjective lens surface and washing off accumulated image distortingdebris 223 uses the display mounted within the vehicle's interior 9Aconnected to the vehicle's data communication network to receive imagesignals for display to the driver. The external image sensor isconfigured to generate an external image display the sensor's externalobjective lens surface 222 is aimed toward the vehicle's exterior (e.g.,rear, front or to the sides of vehicle 8) and the sensor or camera has aselected field of view. The image sensor being substantially exposed tothe ambient environment and accumulated image distorting debris when thevehicle is in use. The image sensor lens washing system is configuredwith laterally offset washing nozzle 230 to selectively spray washingfluid onto the image sensor's objective lens surface at a narrow,glancing angle, the spray being aimed across the field of view along anaiming angle which is aimed at a selected aiming angle that within therange bounded by 1° and 20° in relation to the external objective lenssurface, and the spray being actuated in response to a momentary washcontrol signal of a few seconds duration. The washing system actuationswitch mounted within the interior of vehicle 8 and is configured toselectively and momentarily generate the wash control signal whenactuation of the lens washing system 210 is desired by the driver, whileviewing the display 9A.

Turning now to FIGS. 9-11, a bracket indexed external lens washingsystem 310 is illustrated. As illustrated in FIG. 9, external lenswashing system 310 includes a substantially rigid aiming bracket orfixture 311 having a distal side 311D and a proximal side 311P (bestseen in the cross section view of FIG. 10). Fixture or bracket 311 is arigid durable support fabricated and configured to support camera module312 and thus orients and constrains the camera's external lens which isexposed toward the distal side of assembly 310. The camera's lens has anexternal lens surface 322 with a lens perimeter and a lens central axis350 projecting distally from the lens surface 322, and the lens field ofview is defined as a distally projecting solid angle (e.g., a truncatedcone or pyramid, generating an image signal having, for example, theview in display 209A). The Field of View (“FOV”) typically has anangular width of 90° to 170°. The camera or image sensor 312 has a lenscentral axis 350 centered within the lens perimeter and the lens FOV istypically symmetrical about lens central axis 350.

Washing system 310 includes at least a first nozzle assembly 330configured to be supported and aimed toward the external lens 322 by theaiming fixture 311, and the first nozzle assembly includes a fluid inlet342 in fluid communication with first laterally offset washing nozzle330 which projects above or distally from the aiming fixture's distalside 311D. Laterally offset nozzle 330 is configured and aimed to spraywashing fluid in a substantially planar sheet 336 having a selectedthickness (e.g., 255) toward external lens surface 322 and across thefield of view, spraying at a first selected spray aiming angle (i.e.,preferably spraying in a plane inclined proximally at an angle) of about1°. The selected aiming angle can be in a range between 1° and 20° (asbest seen in FIG. 10) relative to a plane tangent to the lens externalsurface 322. Nozzle 330 is oriented to spray from a selected side,meaning that it is aimed to spray along a first selected spray azimuthangle in relation to a selected fixed reference point or datum 351 onthe lens perimeter.

Preferably, lens washing nozzle 330 includes a first fluidic oscillatorinteraction chamber 331 configured to operate on a selectively actuatedflow of pressurized washing fluid flowing through the first oscillator'schamber 331 to generate a first exhaust flow of fluid droplets 336, andthe first nozzle assembly's fluid inlet 342 receives pressurized washerfluid (e.g., from reservoir 290) and is in fluid communication via fluidpath 340 which passes the pressurized washer fluid distally to the firstlaterally offset outlet nozzle 330 which is configured to exhaust thewasher fluid from the first interaction chamber 331 and generate a firstoscillating spray of fluid droplets 336 aimed toward the external lenssurface 322 and across the field of view. Preferably the fluidicoscillator including interaction chamber 331 is configured as a steppedmushroom fluidic oscillator (as illustrated in FIGS. 12A and 12B). Thepreferred flow rate in oscillating spray 336 is preferably approximately200 ml/min per nozzle at 18 psi, and the spray thickness (i.e., which isseen as thickness in the spray plane transverse to the spray's fan angleplane, as shown in FIGS. 10 and 5B) is preferably approximately 2degrees. The oscillating action and large drops generated by the fluidicoscillator aimed by nozzle 330 in this manner was discovered to wet lenssurface 322 very rapidly and provided a kinetic impact effect which wasfound to impact, dissolve and drive debris (not shown, but like debris223) as part of a flowing effluent laterally off lens surface 222.

Optionally, laterally offset washing nozzle 330 may be configured as anon-oscillating shear nozzle configured to generate a substantially flatfan spray having a selected spray fan angle (e.g., 45° or another angledselected in the range of 15° to 120°). Alternatively, first laterallyoffset washing 33 nozzle may be configured as a non-oscillating bug-eyenozzle configured to generate at least one substantially solid fluid jet(i.e., a substantially solid fluid stream having no fan angle).

Preferably, the laterally offset washing nozzle 330 is configured to aimthe spray 336 from a first selected lateral offset distance (from thenozzle's throat or outlet to the center of objective lens' externalsurface 222, see FIG. 11) of about 15 mm. The selected lateral offsetdistance is preferably within the range bounded by 10 mm and 30 mm, inorder to keep the entire package as compact as possible.

In the embodiment illustrated in FIGS. 9-11 has camera 312 with lens322, a nozzle 330 mounted distally and aiming spray 336 nearly parallelto the lens 322 and associated bracketing (i.e., fixture 311) that isnecessary to hold nozzle 330 in a fixed location relative to the lensboth (in lateral offset and azimuth) from the center line of the lensand distally or above the lens. There are several variables to considerwhen designing for this camera cleaning system and package, including:mounting methods, packaging space, Field of View (FOV) considerationsand Adverse System Effect Mitigation. Taking each in turn:

Mounting Methods

The most preferred mounting or attachment method for the nozzle 330 withthe camera 312 is on the camera module housing or body, directly. Thismounting location assures that no matter where the camera moves, fluidsprayed from the nozzle is always aimed at the right location toward thecenter of the lens surface. A nozzle mounted separately from the cameracould be subject to extra tolerance stackups and become misaimed. It isof course, understood that there will be some camera designs that do notallow for direct attachment and will require separate mounting schemes.The basics of good nozzle placement discussed above are the sameregardless of attachment method.

Packaging Space

In general, the location of cameras (e.g., 312) in vehicles (e.g., 8) islimited to certain specific regions, due to packaging and line-of-sightobjectives. Unfortunately for camera wash nozzle packaging, primevehicle panel exterior locations also tend to be good for othercomponents like; liftgate handles or lighting components. As a result,these vehicle panel exterior locations have very tight packagingconstraints, driving the need for very small nozzles and tightcamera-to-nozzle envelopes.

Field of View Considerations

It should be understood that many existing cameras have Field of ViewAngles from 120 to 170 degrees (e.g., as indicated by radial lines inFIGS. 9-11). A major constraint to system functionality is to havenothing intrude into the displayed field of view of the camera,(e.g.,209A) so that the user is not distracted by the appearance of the lenswashing nozzle 330. Thus the nozzle (e.g., 230 or 330) should belaterally positioned such that it is not in the camera FOV. In theillustrated embodiments of the present invention, the nozzle (e.g., 230or 330) is oriented and aimed from a fixed nearly parallel-to-lenslocation, to be away from and behind the FOV of the camera. As thecamera FOV's approaches and exceeds 180 degrees this will becomeimpossible. However, it will be noted that with these large angles othercomponents in the vehicle will become visible to the camera. It willthen be necessary to place the nozzle (e.g., 230 or 330) such that italigned with the vehicle's other features and is thereby not silhouettedbeyond (and so is “hidden” in the clutter of) the vehicle's exteriorsurface features, minimizing intrusion into “clear” view of the camera.In the embodiment of FIGS. 9-11, nozzle 330 creates a fluid distributionsuch that the entirety, or as much as possible, of the lens is coveredby fluid and impacts the lens at −1 degrees to −20 degrees or so beforethe nozzle head becomes visible to the camera, (“aim angle”). Anothersignificant advantage to nearly parallel impact of the spray 336 to thelens 322 is that the fluid is fully engaged in pushing the debris off orlaterally across the lens, and not in obliquely impact or bouncing offthe lens as would be experienced in higher aim angles, with a moredirect impingement. As the aim angle increases, the nozzle must be moveddistally further and up into the FOV, and farther from the camera,making cosmetically attractive packaging difficult. Therefore, thenozzle should be kept within 10 degrees (aim angle down to the lens) tokeep cosmetic packaging reasonable.

In addition to aim angle considerations, the nozzle distance from thecenter of the lens (as illustrated in FIG. 11) is important. The closernozzle 330 is to the center of the lens 322, the wider the fluiddistribution (and spray fan angle) must be to cover the entirety of thelens. Excessive closeness to the lens center is objectionable for anumber of reasons. Firstly, the nozzle is simply too close to the camerabody and may crash with it physically. Secondly, the wider thedistribution angle (or spray fan angle) needs to be to get goodcoverage. Wider spray fan angles spread a relatively small fluid flowrate over a larger lens cleaning area, which could result in the needfor a different distribution geometry or higher flow rates. Applicantshave found that with one effective distribution geometry, the lateraloffset distance is preferably between 18 mm and 28 mm. This lateraloffset is approximate, as aim angle and nozzle distal height variationstend to complicate the geometry.

Adverse System Effect Mitigation

Addition of cleaning systems (e.g., 310) to vehicle systems can beaccomplished in a number of ways. They can be tied into existingsystems, like rear glass cleaning in an SUV, whereby the camera iscleaned whenever the rear glass is cleaned and vice-a-versa. Systems canalso be designed such that cleaning in on-demand, and requires theaddition of a pump (e.g. 292) and controller or control system (e.g.,9B) programmed to perform the method steps described above. However, itis highly preferable to keep the same number and size of the washerfluid reservoir (s) (e.g., 290). It is highly unlikely that a secondreservoir or fluid bottle would be added to vehicle 8, thus the cameracleaning nozzle system (e.g., 310) is likely to be seen as a parasiticsystem with regard to overall vehicle performance. Since vehiclepackaging generally does not allow for larger washer reservoirs, anycamera cleaning system must consume as little fluid as possible to havethe least impact on the overall vehicle performance.

Since minimizing the overall effect of the addition of the lens washersystem (e.g., 310) to the systems of vehicle 8 is desired, a small flowrate is preferred for the nozzle (e.g., 330). One embodiment used afluidic nozzle with a target flow rate of 200+/−40 mL/min @18 PSI andthis was shown to be very effective in cleaning the lens 322 with theaforementioned packaging guidelines. With these flow and packagingconsiderations in mind, the stepped mushroom circuit of FIGS. 12A and12B was chosen for the preferred fluid delivery geometry embodiment ofFIGS. 9-11. This fluidic circuit (e.g., with stepped mushroom chip 501)is capable of performing well in cold weather conditions with 0.06 mmstep and allows for very small packaging at 5 mm×5 mm for a 200 mL/minflow rate and 50° spray fan angle for spray 336. Most importantly, thisdesign can maintain a minimum 0.014″ power nozzle dimension which isrequired for good clog resistant performance. Power nozzles smaller thanthis risk clogging in automotive situations. The fluidic circuit hasalso been provided with internal filters (e.g., posts 522).Additionally, this circuit design allows for a small interaction region331, approximately 3.3 mm×2.5 mm, helping to support fan angles as highas 50 degrees and still staying within the target packaging space.

The lens washer nozzle assemblies (e.g., 110, 210, 310 or 610)preferably a include fluidic oscillators as part of a nozzle assemblyand preferably a stepped mushroom fluidic oscillator as described incommonly owned U.S. Pat. No. 7,267,290, the entirety of which isincorporated herein by reference. Referring again to FIGS. 12A and 12B,the lens washer nozzle fluidic oscillator is optionally configured as aremovable fluidic chip 501 having an oscillating chamber defined betweenthe fluid impermeable surfaces of chip 501 and the nozzle assembly'schip-receiving interior surfaces (as seen in section in FIG. 10).Referring again to FIGS. 10, 12A and 12B the fluidic oscillator withinteraction chamber 331 as configured in nozzle assembly 310 is suitablefor use at colder temperatures for an exhaust flow in the form ofoscillating spray of fluid droplets 336 and has a pair of power nozzles514 configured to accelerate the movement of the pressurized fluid, afluid pathway that connects and allows for the flow of pressurized fluidbetween its inlet 512 and the power nozzles 514, an interaction chamber518 which is attached to the nozzles and receives the flow from thenozzles, a fluid spray outlet 520 from which the spray exhausts from theinteraction chamber, and a flow instability generating structuralfeature for increasing the instability of the fluid's flow from thepower nozzles, with this structural feature being situated in a locationchosen from the group consisting of a location within the fluid pathwayor proximate the power nozzles. The flow instability generating featurepreferably comprises a protrusion that extends inward from each sidewall506 of the fluid pathway so as to cause a flow separation regiondownstream of the protrusions, but may comprise a step 524A in theheight elevation of the floor of the power nozzles 514 with respect tothat of the interaction chamber, as best seen in FIG. 12B.

Turning now to FIGS. 13A-C, another embodiment for the external lenswashing system and nozzle assembly 610 includes a substantially rigidbezel or aiming fixture 611 having a distal side 611D and a proximalside 611P. Bezel or fixture 611 is configured to support an image sensoror camera 612 and constrain the camera's external lens exposed towardthe distal side; the external lens has an external lens surface 622 witha lens perimeter and a lens central axis 650 projecting distally fromthe lens surface 222, wherein a lens field of view is defined as adistally projecting solid angle (e.g., a truncated cone or pyramid,encompassing the view in display 209A) including the lens central axis650 and originating within the lens perimeter. Washing system 610includes at least a first nozzle assembly configured to be supported andaimed toward the external lens 622 by the bezel or aiming fixture 611,and the first nozzle assembly includes a fluid inlet 642 in fluidcommunication with a first laterally offset washing nozzle 630 whichdistally projects from the aiming fixture's distal side 611D. The nozzle630 is configured and aimed to spray washing fluid in a substantiallyplanar sheet 636 having a selected thickness toward the external lenssurface 622 and across the field of view, spraying at a first selectedspray aiming angle (i.e., preferably spraying in a plane inclinedproximally at an angle) of about 1°. The selected aiming angle can be ina range between 1° and 20° (as seen in FIGS. 13B, 13C and 5B) relativeto a plane tangent to the lens external surface 622. Nozzle 630 isoriented to spray from a selected side, meaning that it is aimed tospray along a first selected spray azimuth angle in relation to aselected fixed reference point or datum 651 on the lens perimeter.

Preferably, lens washing nozzle 630 includes a first fluidic oscillatorinteraction chamber 631 configured to operate on a selectively actuatedflow of pressurized washing fluid flowing through the first oscillator'schamber to generate a first exhaust flow of fluid droplets 636, and thefirst nozzle assembly's fluid inlet 642 receives pressurized washerfluid and is in fluid communication with the first interaction chamber631 which passes the pressurized washer fluid distally to the firstlaterally offset outlet nozzle 630 which is configured to exhaust thewasher fluid from the first interaction chamber and generate a firstoscillating spray of fluid droplets 636 aimed toward the external lenssurface 622 and across the field of view. Preferably, as noted above,that fluidic oscillator is configured as a stepped mushroom fluidicoscillator (as illustrated in FIGS. 12A and 12B). The preferred sprayflow rate is approximately 200 ml/min per nozzle at 18 psi, and thespray thickness (i.e., which is seen as thickness in the spray planetransverse to the spray's fan angle plane, as shown in FIG. 5B) ispreferably approximately 2 degrees. The oscillating action and largedrops generated by the fluidic oscillator aimed by nozzle 630 in thismanner were discovered to wet lens surface 622 very rapidly and provideda kinetic impact effect which was found to impact, dissolve and drivedebris (e.g., like 223, not shown) as part of a flowing effluentlaterally off lens surface 622.

Optionally, laterally offset washing nozzle 630 is configured as anon-oscillating shear nozzle configured to generate a substantially flatfan spray having a selected spray fan angle (e.g., 45° or another angledselected in the range of 15° to 120°). Alternatively, first laterallyoffset washing nozzle may be configured as a non-oscillating bug-eyenozzle configured to generate at least one substantially solid fluid jet(i.e., a substantially solid fluid stream having no fan angle).

Preferably, the first laterally offset washing nozzle 630 is configuredto aim the spray 636 from a first selected lateral offset distance (fromthe nozzle's throat or outlet to the center of objective lens' externalsurface 622) of about 15 mm. The selected lateral offset distance ispreferably within the range bounded by 10 mm and 30 mm, in order to keepthe entire package as compact as possible.

The camera lens washing assembly 610 illustrated in FIGS. 13A-13C ispreferably is configured as an integrated automotive camera module andnozzle assembly, with 612 camera module and the aimed nozzle assemblyintegrally packaged as a one-piece unitary module configured forassembly into a vehicle 8. Substantially fluid impermeable camera module612 is affixed within bezel or housing 611 and has an interiorconfigured to enclose and aim an imaging sensor having an objective lensand a pixelated image sensor array (e.g., like 18), where bezel orhousing 611 is configured to support and aim the camera module 612.Camera module 612 comprises a self-contained and sealed module enclosingthe image sensor array (e.g., like 18) and associated image signalprocessing components (e.g., as illustrated in FIG. 1D), and issubstantially sealed to limit or substantially preclude water intrusioninto the camera module's interior volume. Camera module 612 and integralhousing 611 are configured to be positioned at or affixed upon vehicle 8as a camera lens and lens washer unit 610. Camera module 612 alsoincludes an electrical connector 670 suitable for electricallyconductive connection to a vehicle electrical connector when the cameramodule housing is positioned at the vehicle 8. The camera module'selectrical connector extends to be accessible at a proximal end 672 forconnecting to the vehicle electrical connector (or vehicle controller9B) when the camera module is positioned at the vehicle 8 and cameramodule 612 is responsive to vehicle controller 9B to process videoimages captured by the imaging sensor.

In accordance with the present invention, an integrated automotivesystem, fluidic circuit nozzle assembly (e.g., 210, 310 or 610) areuseful in the practicing method for aiming an oscillating spray to cleanan exterior objective lens surface and allows the driver to determinewhen to clean a soiled external-view camera's objective lens, so thedriver can ensure that the lens is adequately cleaned before moving.

In the lens cleaning system of the present invention, low flow ratefluidic circuit nozzles may be configured to effect bottle cleaningssavings, conservation of fluid, and conservation of pressure.Conservation of pressure is especially important when the camera lenscleaning system is integrated into an existing front wash system, wherethe camera lens washing system must function without detrimentallyaffecting front glass cleaning, especially under dynamic drivingconditions, where the front glass cleaning system's performance ishighly sensitive to fluid pressure. The system and method of the presentinvention is not limited to use with low flow rate nozzles exclusively.Applicants have prototyped a relatively high flow rate nozzle assemblyon an exemplary system and it works well, although the camera's image issomewhat compromised when washing. It appears that the low flow rate isbest accomplished thru a selected fluidic circuit geometry which allowswashing fluid, since droplet size should remain larger when compared toa shear nozzle's non-oscillating spray.

The optimum lens washing nozzle location of the present inventionpresents a very nicely distributed oscillating spray pattern with thefollowing benefits: Allows for nearly flush mounting to the camera lens,means the package does not get longer and interfere, or interfere asmuch, with camera viewing angles as a directed impact nozzle would; andcan be packaged in really close to keep the overall width of the packagefrom growing larger; e.g., a dome-shaped or convex (“bug-eye”) lenswould likely need to have the nozzle spray originate above the lens,angled down, and pushed away from the center line to avoid sight lines,although this would result in a wider and longer package.

The applicants have found that directly spraying nearly parallel to theobjective lens assembly's external surface results in less washing fluid(e.g., water) remaining on the lens after conclusion of spraying,preventing water droplets from forming on the lens and obstructing theview, whereas, in prototype development experiments, a more nearlyon-lens axis or direct impingement spray method is likely to leaveview-obstructing droplets behind.

Having described preferred embodiments of a new and improved lenscleaning system and method, it is believed that other modifications,variations and changes will be suggested to those skilled in the art inview of the teachings set forth herein. It is therefore to be understoodthat all such variations, modifications and changes are believed to fallwithin the scope of the appended claims which define the presentinvention.

What is claimed is:
 1. A remotely controllable image sensor washingsystem with a low-profile nozzle assembly for cleaning a vehicle'sexternal wide-angle image sensor's objective lens surface and washingoff accumulated image distorting debris, comprising: (a) a displaymounted within the vehicle's interior and connected to the vehicle'sdata communication network to receive image signals for display to thedriver; (b) an external image sensor configured to generate an externalimage sensor signal for said display and having an image sensor housingwhich supports an external objective lens surface aimed toward thevehicle's exterior and having a selected field of view, said imagesensor being substantially exposed to the ambient environment andaccumulated image distorting debris when the vehicle is in use; (c) animage sensor lens washing system configured with a compact, low-profilenozzle assembly to selectively spray washing fluid onto said imagesensor's objective lens surface at a narrow, glancing angle, said spraybeing aimed across said field of view along an aiming angle which isaimed at a selected aiming angle that within the range bounded by 1° and20° in relation to said external objective lens surface, and said spraybeing actuated in response to a momentary wash control signal; and (d) awashing system actuation switch mounted within the vehicle's interiorand configured to selectively and momentarily generate the wash controlsignal when actuation of the lens washing system is desired by thedriver, while viewing the display, wherein said low-profile nozzleassembly includes a low-profile conformal housing fixture beingconfigured to wrap around or encircle and support said image sensorhousing and having a fluid inlet in fluid communication with a laterallyoffset washing nozzle head which is supported and aimed by saidconformal housing fixture to spray washing fluid toward said externalobjective lens surface and across said image sensor's field of view atsaid selected aiming angle when activated.
 2. The remotely controllableimage sensor washing system of claim 1, wherein said low-profileconformal housing fixture has a distal side surface opposing a proximalside surface, wherein said distally projecting low-profile nozzle headprojects from said housing's distal surface; said low-profile conformalhousing fixture being configured to wrap around or encircle said imagesensor housing so that said distally projecting nozzle head ispositioned beside and aimed to spray along a transverse spray axis aimedat the center of said distal objective lens surface; wherein saidlow-profile nozzle head is configured to aim a spray issuing from thenozzle's outlet orifice along the spray axis toward the periphery ofobjective lens' external surface, and wherein the lateral offsetdistance between said nozzle's outlet orifice and the periphery ofobjective lens' external surface is selected to be in the range of 2 mmto 10 mm, in order to provide a compact, visually unobtrusive imagesensor and washing system assembly.
 3. The remotely controllable imagesensor washing system of claim 1, wherein said integral nozzleassembly's low-profile nozzle head is configured with a compact fluidicoscillator which, when pressurized with washing fluid, generates a highvelocity spray with a very wide fan angle and so can be placed very nearthe periphery of the lens surface while remaining out of the camera'sview, to provide a very compact and low profile image sensor and washingsystem assembly.
 4. The remotely controllable image sensor washingsystem of claim 3, wherein said low-profile nozzle head's compactfluidic oscillator includes an interaction chamber in fluidcommunication with opposing lateral inlets or fluid feeds configured tooperate on a selectively actuated flow of pressurized washing fluidflowing through the oscillator's chamber to generate an exhaust flow offluid droplets through said outlet spray orifice, said oscillator beingsupported with the oscillator's orifice centered on a spray axis aimedat the lens surface, wherein said compact fluidic oscillator has anaxial length along the spray axis of about 3 mm.
 5. The remotelycontrollable image sensor washing system of claim 4, wherein saidcompact fluidic oscillator with opposing lateral inlets comprises alateral feed reverse mushroom fluidic oscillator.
 6. The remotelycontrollable image sensor washing system of claim 43, wherein saidcompact fluidic oscillator with opposing lateral inlets comprises atwo-sided lateral feed mushroom fluidic oscillator.
 7. The remotelycontrollable image sensor washing system of claim 6, wherein saidcompact fluidic oscillator has a fluid channel inlet segment in fluidcommunication with at least a pair of power nozzles configured toaccelerate the movement of pressurized fluid that flows through saidpower nozzles so as to form a jet of fluid that flows from each saidpower nozzle, all being part of a fluid channel pathway that connectsand allows for the flow of said fluid between said inlet and said powernozzles; wherein said fluid channel pathway is defined between boundarysurfaces that include a pair of sidewalls, said interaction chamberattached to said nozzles and which receives said jet flows from saidnozzles, wherein said outlet orifice exhausts spray from saidinteraction chamber, and wherein said fluid channel pathway alsoincludes a flow instability inducing feature configured to increase theinstability of said flow from said power nozzles, said flow instabilityinducing feature being configured within said pathway at a locationupstream of said power nozzles.
 8. The remotely controllable imagesensor washing system of claim 7, wherein said flow instability inducingfeature comprises a pair of protrusions that extend inward from saidfluid pathway boundary surface, said protrusions configured to cause aflow separation region downstream of said protrusions.
 9. The remotelycontrollable image sensor washing system of claim 3, wherein saidfluidic oscillator is configured to generate an oscillating spray ofhigh velocity fluid droplets in a flat, fan-shaped spray pattern havinga selected fan angle so that said droplets impact substantially theentire external objective lens surface.
 10. The remotely controllableimage sensor washing system of claim 9, wherein said oscillating spray'sselected fan angle is selected to be in the range 50° to 90° so thatsaid droplets impact substantially the entire external objective lenssurface.
 11. The remotely controllable image sensor washing system ofclaim 3, wherein said distally projecting low-profile nozzle headdefines a cavity in fluid communication with said conformal housing'sinternal fluid transmission lumen and providing fluid communication froma conformal housing fixture fluid inlet; and wherein said nozzle headcavity has first and second lateral openings which are in fluidcommunication with said housing's internal fluid transmission lumen. 12.The remotely controllable image sensor washing system of claim 11,wherein said compact fluidic oscillator is configured as a removableinsert having a first surface, a second surface opposing the firstsurface, a left side surface and a right side surface; and wherein saidfluidic circuit oscillator's interaction chamber and other features aredefined in at least one of said insert's surfaces.
 13. The remotelycontrollable image sensor washing system of claim 12, wherein saidinteraction chamber has opposing lateral inlets or fluid feeds definedin said inserts left side surface and said right side surface; andwherein said nozzle head cavity's first and second lateral openings arein fluid communication with said insert's opposing lateral fluid feedsdefined in said insert's left side surface and said right side surfacewhen said insert is installed in said cavity; and wherein said nozzlehead is configured to provide a selectively actuated flow of pressurizedwashing fluid through the oscillator's chamber when said insert isinstalled in said cavity and said oscillator being supported with theoscillator's orifice centered on the spray axis.
 14. The remotelycontrollable image sensor washing system of claim 13, wherein saidoscillator insert has an axial length along the spray axis of about 3mm.
 15. The remotely controllable image sensor washing system of claim14, wherein said oscillator insert comprises a lateral feed reversemushroom fluidic oscillator with the lateral inlets and the interactionchamber defined in either the first surface or the opposing secondsurface of the insert.
 16. The remotely controllable image sensorwashing system of claim 15, wherein said oscillator insert comprises atwo-sided lateral feed mushroom fluidic oscillator having theinteraction chamber defined in the insert's first surface; wherein theopposing lateral inlets or fluid feeds defined in said inserts left sidesurface and said right side surface which are in fluid communicationwith a fluid channel inlet segment defined in the insert's secondsurface; and wherein said fluid channel inlet segment defined in saidsecond surface is in fluid communication with said interaction chamberdefined in said top surface when said insert is installed in saidcavity.